Changes in agricultural production methods have been associated with environmental pressure and a loss of natural habitats. This paper explores the extent to which farmer participation in off-farm work (an increasing phenomenon in most developed countries) changes the intensity of agricultural input use focusing, in particular, on fertilizer and crop protection product use. A sample selection model that accounts for both unobserved heterogeneity between farms and the potential simultaneity between farm operations and hours worked off-farm is estimated for 2,419 farms in England and Wales. The econometric evidence indicates that the input intensity of products which have well-established links to environmental damage can increase as well as decrease. The results suggest that that fertilizer intensity may decline as off-farm labor increases while the use of crop protection per hectare increases as off-farm work increases. Copyright Springer 2006crop protection, farm household model, fertilizer, input intensity, multifunctionality, off-farm work, panel, Q53, Q12, Q24,